The present invention relates to a liquid holding tank which will prevent spillage when a liquid is sloshed around therein.
The U.S. Navy has demonstrated that marine mammals, such as porpoises and seals, are highly successful in performing salvaging operations. These operations are accomplished by fitting the mammal with a grabber device which normally protrudes in front of his nose. Upon command the mammal will dive to the bottom of the ocean, attach the grabber device to an object to be retrieved, and return to the surface. The grabber device, which is normally tethered to a surface ship, can then be utilized to retrieve the object.
In many of these salvaging operations the mammals are transported on a surface ship to a remote location where the object is located. Sometimes the travel time amounts to many days at sea, during which time the mammals must be cared for with much concern. In the past the porpoise has been kept on a stretcher out of water on the ship with water being sprayed onto the animal periodically. This approach has two major limitations, namely: (1) the mammal can stay out of the water only a few days, and (2) the mammal has no freedom of movement which actually causes a stiffening of his body.
The ideal arrangement would be for the animal to be located in a holding tank aboard the ship. Since ships are not normally equipped with such holding tanks the only other alternative is to provide a portable tank which can be carried on and off the ship as required. In the past, such a tank has appeared impractical because of its size and weight, and the sloshing out of the water from the tank will occur when the ship is in heavy sea states. The present invention makes the portable tank concept feasible and highly desirable. This has been accomplished by providing a lightweight tank which can be easily packaged, and utilized aboard ship to contain the mammal without any substantial sloshing of the water over the top rim of the tank.